Update README.md

You should append .finish method to new Rack::Response object.
We want to use a delimiter agnostic path generator
Merge pull request #576 from mateuszkosmider/master

Update README.md
Merge pull request #577 from krainboltgreene/patch-1

We want to use a delimiter agnostic path generator
fix OPTIONS regression. fixes #573
remove offending line
README: more consistent delimiter agnostic paths
Merge pull request #582 from stevschmid/573-fix

Fix OPTIONS regression
Merge pull request #584 from goldcaddy77/readme-agnostic-paths

README: more consistent delimiter agnostic paths
Do not repeat the same error messages
Add tests for not repeating the same error messages
Update CHANGELOG.md
Fix after boot thread-safety issue
Merge pull request #585 from SPBTV/thread-safety

Fix after boot thread-safety issue
Merge pull request #586 from kiela/master

Do not repeat the same error messages
Fix oauth2 middleware compatibility with draft-ietf-oauth-v2-31 spec.
uses_path_versioning? should return a bool

as stated on the test
https://github.com/arthurnn/grape/blob/01f2590741120b613a19a57836c2e05608ac586b/spec/grape/path_spec.rb#L60
that method should return +true+ or +false+
Use be false instead of be_false
Use be true instead of be_true
use flat_map instead of map.flatten